Not Applicable
Not Applicable
1. Field of Invention
This invention pertains to a portable lifting device. More particularly, this invention pertains to a device having a base and articulated arms for lifting and moving items with minimal effort by an operator.
2. Description of the Related Art
The standard shovel, spade, and snow scoop requires both hands of the operator and places great stress on the back of the operator. Various means for aiding the operator have been invented to ease the burden placed on the operator during lifting. These means include adding lever arms to the shaft and changing the shape of the shaft.
U.S. Pat. No. 2,419,015, issued to Gascoigne, et al., on Apr. 15, 1947, titled xe2x80x9cAgricultural Implement,xe2x80x9d discloses a digging implement, such as a spade or fork, having a spring-loaded attachment that comes into contact with the surface after the implement is inserted into the ground. The implement has a shaft A1 with a tool head A at one end and an extension handle A3 at the other end. The extension handle A3 is desirable because of the automatic action produced by the spring D.
Once the implement is in the ground, the attachment serves as a spring-loaded lever, allowing the implement to lift a quantity of soil. The attachment is fixed to the implement shaft A1 with an eye Bx engaging an eye A5 on a collar A4 fixed to the shaft A1, which allows the implement shaft A1 to tilt relative to the attachment and to rotate relative to the attachment. The lever action is due to the tilting allowed by the eye-in-an-eye assembly A5-Bx, and it is assisted by the spring D, which adds a lifting force to the tool head A. A chain E is provided to limit the action of the spring D on the attachment. The raised soil load is dumped by swinging the implement shaft A1 laterally and then rotating the shaft A1, allowing the soil to slide off the tool head A. The Gascoigne, et al., tool has the disadvantage of not providing a stable connection at the shaft A1 due to the inherent nature of the eye-in-an-eye assembly A5-Bx.
Over the years following the issuing of the Gascoigne, et al., patent, various other patents have issued for digging tools with some form of lifting aid. A representative sampling includes the following. U.S. Pat. No. 4,461,458, issued to Poulin on Jul. 24, 1984, titled xe2x80x9cLow Effort Digging and Lifting Tool,xe2x80x9d discloses a lever arm 28 pivotally connected to a shovel head 25 with a pivot 24. The lever arm 28 is pivotally connected to a foot plate 33 having a cleat 34.
U.S. Pat. No. 4,722,512, issued to Lighthizer on Feb. 2, 1988, titled xe2x80x9cHand Operated Digging Tool Comprising a Ground Penetrating Portion,xe2x80x9d discloses a lever arm 12 hingedly attached to the back of the shovel 10 adjacent to where the shovel 10 engages its handle 11. The lever arm 12 assumes a desired approximately 45xc2x0 angle with the back of the shovel 10 because of the positioning of the extension 14, which projects from the lever arm 12 and contacts the back of the shovel 10. In operation, the lever arm 12 is held against the shovel handle 11 by a magnet 15. The lever arm 12 is released from the magnet 15 when the shovel 10 strikes the soil, as in digging, and the arm 12 is captured by the magnet 15 when the shovel is levered such that the shovel handle 11 is positioned parallel to the ground.
U.S. Pat. No. 4,881,332, issued to Evertsen on Nov. 21, 1989, titled xe2x80x9cShovel Lifting Aid,xe2x80x9d discloses another variation of a lifting lever 16 attached to a handle 11 of a shovel 12. The lifting lever 16 is attached to the shovel handle 11 by a pivot handle attachment mechanism 17. The mechanism 17 includes a sleeve 30 inside a sleeve 26. The inner sleeve 30 is secured to the handle 11 by a screw clamp 31, 32. The screw clamp 32 passes through a slot in the outer sleeve 26, thereby allowing the outer sleeve 26 to freely rotate about the inner sleeve 30.
U.S. Pat. No. 6,203,081, issued to Kegan, Sr. on Mar. 20, 2001, titled xe2x80x9cEasy Lift Levered Shovel,xe2x80x9d discloses a levered fulcrum 18 pivotally attached to the shaft 16. The movable clamp 22 positions the levered fulcrum 18 at any point on the shaft 16 by way of a nut and bolt arrangement 24. The levered fulcrum 18 is spring-loaded by a spring 28 to maintain the fulcrum 18 in a nested position. The operator pivots the lever against the resiliency of the spring 28 rearwardly away from the shank 16 such that the fulcrum 18 rests on the ground.
An objective of this invention is to provide a lifting tool that requires minimal effort from the operator, provides a stable platform for the lifted load, and can be operated at a convenient height, minimizing bending by the operator.
It is a further objection of this invention to enable those confined to a wheelchair to lift items that otherwise would not be lifted.
According to one embodiment of the present invention, a portable hand-operating lifting device is provided. The device includes a lifting head, which in one embodiment is a shovel blade, and a lifting shaft having a handle at the end opposite the lifting head. A lever arm is attached between the lifting head and the lifting shaft. The lever arm is pivotably and swivelly connected to a cleated foot plate. The foot plate has a lifting plate, which allows the operator to remove the foot plate from the surface and reposition the foot plate such that the lifting device can be used in a different location.
In one embodiment, the handle is adjustable in that the distance between the handle grip and the lifting head can be extended or shortened. In another embodiment, the angle of the lifting handle relative to the lifting shaft is adjustable. In still another embodiment, the angle of the lifting shaft relative to the lifting head is adjustable.